Rf energy retaining raceway for communications cables



Feb. 20, 1968 c, o. ME|$KLE 3,370,121

' ENERGY RETAINING RACEWAYlfi 'ORCOMMUNICATIONS CABLES Filed Jun 26,1967 United States Patent 3,370,121 RF ENERGY RETAINING RACEWAY FORCOMMUNICATIONS CABLES Claude 0. Merckle, Hagerstown, Md., assignor toThe Danzer Metal Works Co., Inc., Hagerstown, Md., a corporation ofMaryland Continuation-impart of application Ser. No. 441,149, Mar. 19,1965. This application June 26, 1967, Ser. No.

5 Claims. (Cl. 174-35) ABSTRACT OF THE DISCLOSURE An RF energy retainingraceway for communications cables which includes trough-like racewaysections into which cables are laid and detachable covers for theraceway sections. A connector unit for adjacent raceway sectionsconsists of a short trough-like member which interfits with the ends ofthe adjacent pair of raceway sections and has positive interlockingengagement therewith. A bridging element spans the top of the shorttrough-like member and provides a firm seat for opposed terminal endportions of the adjacent covers. Metallic RF energy retaining gasketingextends in a continuous band around the connector unit and between allcovers and their underlying raceway sections.

Cross-reference to related application This application is acontinuation-in-part of my prior copending application Ser. No. 441,149,filed Mar. 19, 1965, for Raceway for Electrical Cables and Wires Adaptedto Retain RF Energy.

Background of the invention As explained in said prior application,there is a need for an eflicient RF energy retaining raceway of the typepermitting cables to be conveniently laid into the same so as to permitready access to the cables at all points along the raceway system. Thecritical element of such a raceway system is the connector joint betweenadjacent sections of the system and this joint most be constructed so asto be absolutely RF energy tight, while at the same time affording asturdymechanical connection between the raceway sections which can beseparated when necessary. I

The above needs are found lacking in the prior art to a great extent andare generally satisfied in the mentioned prior application. The generalpurpose of the invention herein is to provide a significant improvementover the construction in the prior application particularly concerningthe connection or joint between adjacent raceway sections, rendering theassembling of the system more convenient and fool-proof and somewhatsimplifying the manufacturing of parts due to the provision of partswhich are uniform in construction and interchangeable.

Summary of the invention The invention comprises an essentially U-shapedconnector member having interfitting engagement with the ends of a pairof adjacent trough-like raceway sections. Separable fastener meanspositively retain the raceway sections and connector member ininterlocking engagement. The raceway sections carry removable coverswhose terminal ends overlie the connector member and span the sametransversely. In accordance with the invention, a stiff bridging pieceor channel spans the open top of the connector member and provides afirm seat for the metallic gasketing which extends transversely of thecovers at their ends, enabling the cover constructions to be identicaland interchangeable with no right or left hand or 3,370,121 PatentedFeb. 20, 1968 male and female non-interchangeable constructions ofparts. The invention construction results in increased economy,reliability and ease of assembling by non-skilled personnel.

Brief description. of the drawing Description 0 the preferred embodimentIn the drawings, wherein like numerals are employed to designate likeparts, the numerals 10 and 11 designate a companion pair of generallyU-shaped trough-like opentop raceway sections formed of sheet metal andconstructed in accordance with the description in said priorapplication. Each raceway section includes apair of side flatlongitudinal covermounting flanges 12 which project outwardly of thevertical side walls 13 of the raceway sections. Generally flat sheetmetal covers 14 of identical and interchangeable construction areprovided for the raceway sections and these covers are constructedgenerally in accordance with the teachings ofsaid prior application andserve generally the same purpose in the invention, namely, for renderingthe tops of the trough-like raceway sections RF energy tight andallowing easy access to the cables laid in the raceway system. However,a significant improvement over the corresponding covers for the racewaysections in the prior application resides in the fact that the opposingends of the covers 14 are identical, thus eliminating right and lefthand parts or male and female parts as was necessitated with the coversin the prior application. The covers 14 have downturned side stiffeningflanges 15 formed integral therewith which lie outwardly of the mountingflanges 12 in assembly. Transverse angle braces 16 may also be weldedacross the opposing transverse ends of the covers 14 for increasedrigidity and this arrangement was depicted and described in said prio-rapplication.

A short essentially U-shaped connector member 17 is provided fordetachably joining the adjacent raceway sections 10 and 11 and thisconnector member has top outwardly extending side flanges 18 whichunderlie the flanges 12 in assembly. As disclosed in said priorapplication, the connector member 17 includes an interior relativelynarrow U-shaped member 19 which extends continuously over the bottomwall 20 and vertical sides 21 of the connector member and is spacedequidistantly inwardly of the edges of the connector member, as shown. Astill narrower U-shaped metallic spacer element 22 is intervened betweenthe connector member 17 and the interior U-shaped member 19 and thethree elements are rigidly connected by welding or the like, asdescribed in said prior application. The spacer 22 also extendscontinuously over the bottom and sides of the connector member. At thetop of the interior U shaped member 19, a pair of short inwardlydirected horizontal support flanges 23 are formed at the same elevationas the flanges 18 for the support of a transverse horizontal bridgepiece or channel 24 whose ends rest upon the flanges 23 in assembly.These elements are all formed of metal. The elements 23 and 24 are notdisclosed in said prior application and constitute important parts ofthe present invention enabling the ends of the covers 14 to beidentically formed and eliminating the male and female cover ends of theprior application.

As fully explained in the prior application, the opposing ends ofraceway sections 10 and 11 interfit telescopically with the connector17, said ends of the raceway sections 3 entering the cavities formed onopposite sides of the U- shaped spacer'22 and between the interiormember 13 and the main exterior wall of the U-shaped connector.

Also, as fully disclosed in said prior application, a section ofmetallic gasketing such as knitted Monel metal gasketing indicatedgenerally at 25 extends continuously between the interior U-shapedmember 19 and the outer wall of connector 17. This gasketing hasterminal end portions or pads 26 which lie upon the flanges 18 and thegasketing is divided longitudinally into branches 27 which extendcontinuously on opposite sides of the spacer element 22. The arrangementis such that the ends of raceway sections and 11 will electricallycontact the opp'osite edges of the gasketing 25 while within thecavities formed by the spacer element 22. This electrical contact iscontinuous along the U-shaped configuration of the connector andgasketing.

Additionally, as shown in the drawings and in the prior application,each cover 14 has secured to its bottom face side longitudinalcontinuous metal gasket sections 28 and supporting boundary strips 29 ofrubber-like material adhesively secured to the cover. The gasketing 28contacts the flanges 12 in assembly and is compressed between theseflanges and the rigid cover. The transverse ends of each cover alsocarry sections 30 of the same compressible metal gasketing andsupporting strips or sections 31 of rubber-like material adhered to thecover 14. As shown in FIGURE 2, the metal gasketing sections 30 areadjacent the transverse edges 32 of the covers 14 and these gasketingsections abut and contact laterally in assembled relationship,.Referring to FIGURE 2, the transverse gasketing sections 30 liedirectly upon and electrically contact the rigid bridge piece 24 and arecompressed against the same. The gasketing sections 30 extend for thefull length of the bridge piece 24 and somewhat beyond the ends of thebridge piece so that end portions of the sections 30 will lie upon andelectrically contact the terminal pads 26 in assembly, substantially asdisclosed in said prior application. However, the provision of thebridge piece 24 and supporting flanges 23 constitutes a distinctimprovement over the construction in the prior application where no suchbridge piece was employed. In the prior arrangement, one of the covers14 was required to carry a projecting extension or lip to engage underand support the transverse gasketing on the ends of each pair of coversat each raceway joint or connection. Consequently, the covers were notinterchangeable and required male to female construction and engagement,whereas the present arrangement renders the covers identical andinterchangeable and also provides a more .reliable and rigid seat orsupport for the transverse cover gasketing sections 30.

Additionally, the bridge piece 24 is easily removable but cannot becomedisplaced in any direction when the parts are assembled, as shown inFIGURE 2. In all other respects, the construction of the raceway may beidentical to the construction disclosed in the prior application and itshould not be necessary to redescribe the entire raceway system indetail herein because the essential improvement, as stated, resides inthe provision of the bridging piece 24 and associated parts permittingthe simplification and standardization of the raceway covers.

The parts are rigidly and detachably connected together in assembledrelationship in exactly the same manner disclosed in the priorapplication. The several drive ins or connectors 33 engage throughapertures 34 of the interfitting flanges 12 and 18 and underlyingcoacting bracket parts 35 and 36 carried by the sections 10 and 11 andthe connector 17, respectively. The elements 33 and the apertures 34 lieentirely outside of the boundaries of the cover gasketing so as not topenetrate or interfere with the same and also outside of the ends of thebridge piece 24. The covers 14 are quickly releasably secured to theirmounting flanges 12 by the same quarter-turn quick release fasteners 37,shown and described in said prior 1- application. The raceway covershave slots 38 to receive the heads of the fasteners 37 and these slotsand heads also lie outwardly of the metal gasketing on the bottom facesof the covers so that the action of the gasketing in retaining RF energyor preventing its escape from the raceway is not impaired. The fasteners37 throughout the system cause firm and uniform compression of the metalgasketing along the opposite sides of the covers 14 and across theirends which overlap or overlie the rigid bridge pieces 24.

In light of the above, it is believed that the nature of theimprovements may be fully understood with reference to the priorapplication and no further description or illustration should berequired. It is also thought that the advantages of the improvedconnector or joint for the raceway system will be readily appreciated bythose skilled in the art.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as a preferred example of the same, and thatvarious changes in the shape, size and arrangement of parts may beresorted to, without departing from the spirit of the invention or scopeof the subjoined claims.

I claim:

1. In an RF energy retaining raceway for communications cables, a pairof raceway sections each being trough-like and having an open top,identical covers for the raceway sections and being substantiallycoextensive therewith, a connector connecting the opposed ends of saidpair of raceway sections and being of like cross sectional shape withthe raceway sections and having interfitting engagement with the ends ofthe raceway sections, a separate substantially rigid bridging piecespanning the connector transversely at its top, end portions of anadjacent pair of covers overlying the bridging piece and projectingbeyond the opposed ends of the raceway sections, a section of metallicRF energy shielding gasketing on the connector and following thetransverse cross sectional shape of the connector and being inelectrical contact with the ends of the raceway sections substantiallythe full length of the section of gasketing, additional metallic RFenergy shielding gasketing between the covers and raceway sectionsincluding transverse sections of gasketing extending across the coversat their ends and lying upon the bridging piece, releasable fastenermeans disposed outside of the gasketing and detachably securing theraceway sections and said connector in assembled relationship, andfastener means releasably securing the covers to the raceway sections.

2. In an RF energy retaining raceway for communications cables inaccordance with claim 1, outwardly projecting side flanges on theraceway sections and connector, terminal pads of metallic RF energyshielding gasketing on the side flanges of the connector andconstituting extensions of said section of gasketing on the connectorand projecting beyond the opposite ends of the bridging piece, supportelements for the bridging piece on the connector projecting inwardly ofthe side flanges of the connector, and said transverse sections ofgasketing extending beyond the ends of the bridging piece andelectrically contacting and lying upon said terminal pads.

3. In an RF energy retaining raceway for communications cables inaccordance with claim 2, wherein said support elements for the bridgingpiece comprise short horizontal flanges disposed at the same elevationas the side flanges of the connector, and said bridging piececonstituting a channel section including dependent side webs straddlingthe short flanges.

4. In an RF energy retaining raceway for communications cables inaccordance with claim 1, and wherein said connector is substantiallyU-shaped and includes an outer wall and an interior wall which isnarrower than the outer wall and spaced equidistantly inwardly from theedges of the outer wall, an intermediate U-shaped spacer element betweenthe outer and interior walls and being substantially narrower than theinterior wall and arranged near the lateral center of the interior wall,Where-by cavities are provided between the outer and interior walls onopposite sides of the spacer element for the reception of the opposingends of the raceway sections, said section of metallic gasketing on theconnector being divided into branches disposed on opposite sides of thespacer element and terminating in horizontal pads at the top of theconnector projecting outwardly of the outer wall of the connector, sideflanges on the connector underlying said pads and supporting them, shortinwardly extending flanges carried by the top of the interior wallsubstantially at the elevation of the side flanges, said rigid bridgingpiece having its ends resting upon and supported by said short flanges,said transverse sections of gasketing extending beyond the ends of thebridging piece and overlying said pads and being in electrical contacttherewith.

5. In an RF energy retaining raceway for communications cables inaccordance with claim 1, and wherein said transverse sections ofgasketing, extending across the covers at their ends have theiroutermost edges substantially registering with the end edges of thecovers, whereby the end edges and transverse sections of gasketingsubstantially abut.

No references cited.

DARRELL L. CLAY, Primary Examiner.

